Award will help professors expand the frontiers of 3-D printing

The National Science Foundation has awarded a $1.2 million, three-year grant to four professors in the Department of Chemical and Biomolecular Engineering for a project that has potential to advance the frontiers of 3-D printing. Charles Sing, Ying Diao, Damien Guironnet, and Simon Rogers intend to create a platform for designing advanced materials that allows makers to tune the structure and function of a material on-the-fly.

Not long after arriving on campus, the team of investigators, each an assistant professor with a different research background and set of skills, got together to brainstorm what intriguing challenges they could solve together. Take camouflage. Camouflage is only effective as long as the person wearing it remains crouched in the jungle or standing by a sand dune in the desert. What if you had a material that could provide camouflage in many different environments, and you control how it works? Chameleons change color by adjusting skin structure at nanometer-length scales. Could humans design something similar with advanced materials processing?

“What we’re talking about is making a device, an object, instrument, from ostensibly the same material. It has different properties in different parts of the material,” Rogers said. Imagine a Lego brick that has one transparent wall, but the brick is made from all the same material. There’s one material with different properties, and the maker controls the material’s properties.

The project has two overarching goals: develop a screening method for versatile, 3-D printable block copolymer materials, which are two or more different polymer chains linked together; and screen to optimize flow-based tuning of morphology in 3-D printed materials. That entails testing their hypothesis that tuning the flow in 3-D printing will allow for on-the-fly or on-demand manipulation. Insights gained from their research could have potential applications in camouflage, antireflection coatings, metamaterials and displays.

For this project, each faculty member brings a distinct set of skills and expertise. Charles Sing, who works in molecular simulation and theory, will provide what he described as a treasure map. His research will guide the synthesis that occurs in the lab of Damien Guironnet, the self-described “cook.” Because Sing will be predicting some of the molecule’s properties beforehand, Guironnet will be able to synthesize the molecules that will make the polymers with the unique structure needed for the process.

From there, the material is handed over to Simon Rogers and members of his lab, who carefully control different flow conditions and investigate how the structures reorganize. Rogers then feeds information gleaned from his experiments and analysis to Ying Diao’s group. Diao will take the novel molecule and, with the knowledge of how this material reacted to Rogers’ experiments, she will attempt to make a functional material using 3-D printing.

Rogers then feeds information gleaned from his experiments and analysis to Ying Diao’s group. Diao will take the novel molecule and, with the knowledge of how this material reacted to Rogers’ experiments, she will attempt to make a functional material using 3-D printing.

“One key issue we’re interested in is the assembly, how to direct the assembling of the materials because it’s critical to the function,” Diao said. “In this case, we’re interested in the photonic properties. Can we potentially make camouflage using this functional material by assembling the material into highly ordered structures? We’ll be able to sensitively modulate the structure over length scales predicted by Charles Sing.”

What they’re doing could be called a “high-risk, high-reward” type of project, Diao said, because proposing to physically change structure on the fly is a fairly new idea. “The challenge is, how the assembly of this novel class of materials respond to flow is previously unknown. Flow-directed 3D printing is also not demonstrated before and requires significant innovation to realize,” she said.

Faculty anticipate discoveries and some surprises along the way because the material they’ll be working with is new and the process, called non-equilibrium processing, is still a relatively new concept, they said.

What makes the project unique is each investigator has a role to play in each other’s research. Due to the iterative, multi-project investigator structure, there will be a lot of coordination involved and each faculty member will need to understand results from their colleagues to be able to apply it to their own research.

“It’s an exciting challenge,” Guironnet said. “We get the opportunity to understand each other’s work to increase the impact of our own research. And at the same time, I get to extend my expertise as well,” he said.

What’s also unique about the group is that each investigator is an assistant faculty member. They all joined the department within about a year of each other.

“Because we’re new professors, there’s been a focus on building our own reputations, our own lab expertise. This is our moment to do something bigger than that, and that is extremely exciting,” Sing said.

Thanks to the NSF funding, faculty also plan to expand their outreach projects in computation, characterization and synthesis, via the Girls’ Adventures in Math, Engineering and Science (GAMES) summer camp and the St. Elmo Brady STEM Academy, which exposes underrepresented elementary students to STEM fields.